Utility central baseload plus distributed Solar peak generation Rooftop Solar enhances Utility economics
Distributed rooftop Solar from residential customers • Safe, easy, and affordable • Unstoppable national trend (42 states ahead of Kansas) • Real savings for utilities, municipalities, rural electrics
PV’s place on the grid Good planning requires accurate information • Utility Myth 1: Solar “contributes nothing” • Utility Myth 2: Solar customers are “free riders” on the grid • Utility Myth 3: Utility scale arrays are the most cost-effective • Fact: Kansas needs baseload wind power and the distribution system • Fact: Utilities will remain critical to solar growth
Evergy’s argument Solar peak doesn’t match residential peak, so “excess solar power is worth only the avg cost of fuel: 3.4 cents/kWh” Solar “DG customers are not buying enough electricity to pay their full fixed costs and are thus being cross- subsidized by the other residential customers.”
Utility Myth 1: Missing the peak, residential Solar “contributes nothing” When a family leaves for work or school in the morning, the house may go empty. But the strip mall, neighborhood school, and office buildings light up. When the people return home, the offices go dark. Excess power is shared all the time. FACT: A utility feeder & substation serves all customer classes, not just residential
Example: Medium businesses Concrete Plant Substation Source : Load curve graphs are from “The Impact of Dynamic Pricing on Westar Energy‘, Dr. Ahmad Faruqui, Smart Grid and Energy Storage Roundtable, Brattle Group, September 18, 2009. Solar profile is superimposed.
Utility Myth 2: Solar customers are “free riders” on the grid
Like advertising at the Super Bowl, hours of high demand are expensive: Almost 4 times the cost for utilities to generate and distribute as off-peak power 23.4₵/kWh 6.1₵/kWh
Critical Peak Periods (CPP) are afternoons of the hottest 15 days of the year 89.5₵/kWh 5.6₵/kWh
What’s the average Peak kWh worth today? • My Westar peak price graphs are from 2009. Generation chases Demand Fracking has reduced so utilities try to modify natural-gas prices, but… customer behavior • Fuel costs are no longer Time-of-Use pricing (TOU) key. tries to fairly assign the costs • Capital costs of oversizing of electricity to the hours it is the generation, least and most expensive to transmission and generate and distribute. distribution hardware are the main factor
2018 KCC/Westar Time-of-Use Pilot Rates Charge Time Cost Customer Charge $18.50 Energy Charge Winter Period - Energy used in the billing months of October through May On-Peak Weekdays 10:00 AM - 8:00 PM 9.5205 ₵ kWh Off-Peak Weekends, Holidays, All Other Hours 5.8875 ₵ kWh Summer Period - Energy used in the billing months of June through September On-Peak Weekdays 1:00 PM - 8:00 PM 16.3105 ₵ kWh Intermediate Peak Weekdays 10:00 AM - 1:00 PM 11.1945 ₵ kWh Off-Peak Weekends, Holidays, All Other Hours 7.1611 ₵ kWh Plus all applicable adjustments and surcharges 4.06 Source: Westar 2018 Rate Application
Value of Solar generation from the KCC- Westar TOU Pilot Study 63₵ kWh? 43₵ kWh? 11.2₵ 16.3₵ kWh kWh 7.2₵ kWh July 15 th Sunrise 6:12 Sunset 8:51
If you agree that Time-of-Use Pricing is a benefit to utilities and all ratepayers: TOU Solar Peak Generation • You have to make it • Peak generation is convenient to dry governed by the sun’s clothes by limiting it to path. It generates from practical hours, 1-7 PM 10 AM to sundown, regardless of human • Continued compliance behavior. requires retraining new • Once a system is customers as they move in and out of a utility’s installed, it offsets peak territory load through its entire lifetime of 25 years.
How much would an Evergy customer be worth who reduces their peak consumption by over 80% on all the hottest days … for 25 years? Conclusion: Solar energy is worth far more than 3.4 cents/kWh.
Utility Myth 3: Utility scale arrays are more cost-effective than rooftop Solar • The sunlight landing on 10 acres near Hutchinson is the same as that landing on a collection of rooftops with the same total area, spread around Evergy’s territory. • So the generation profile of a utility-scale array would fit Evergy’s needs in the same way that rooftop solar does.
…except for Peak Load distribution Evergy (Westar and Great Plains Energy) owns …about 28,100 miles of distribution lines. Through 2023, Evergy investments in transmission and distribution will be 70% greater than for generation. Source: Evergy 2019 Investor Presentation Pacific Gas & Electric found that its typical feeder is used over 50% of capacity …only 40% of the time. There is a lot of investment that is not being used. If much of the peak can be generated where the electricity is being used, what savings might be available for everyone?
Recent Distribution Studies USA A 2018 study of a range of commercial buildings found that a combination of site-based solar, and a storage system of only 20% of the buildings’ demand Source: Lawrence Berkley National Laboratory
Holland A 21-40% reduction of T&D demand can bring a 45-72% reduction of distribution hardware costs …to all rate payers. * Evergy has 32 customers/mile of line Kansas Electric Cooperatives…….3.2/mile
Distribution benefits are greater the closer to the end-user the peak is generated & stored Rooftop solar = maximum benefits Community solar = mixed benefits Utility-scale solar = centralized resource; few benefits Testing this theory It would be as simple as allowing a representative number of solar customers to join KCC/Westar TOU Pilot Study
We need to change course,
Yr Mo Day Time Wind Spd Cloud Temp Survey of Kansas’ 201208030652 120 3 BKN 84 renewable 201208030752 140 6 SCT 82 201208030852 80 3 CLR 82 resources 201208030952 *** 0 CLR 81 201208031052 *** 0 CLR 79 2012 was a brutally 201208031152 *** 0 CLR 79 201208031252 *** 0 CLR 82 hot year, at 14 201208031352 150 7 SCT 84 weather stations in the 201208031452 170 6 CLR 85 eastern 2/3 of Kansas 201208031552 180 5 SCT 84 201208031652 180 5 SCT 88 This is a typical day: 201208031752 180 7 CLR 90 201208031852 *** 0 CLR 92 Evergy Defined Peak Load 201208031952 140 8 CLR 97 201208032052 140 6 CLR 100 Yellow: Cloud cover during the 201208032152 170 8 CLR 103 daylight hours of those days 201208032252 200 8 CLR 106 201208032352 200 6 CLR 103 Red: Hours over 100⁰F 201208040052 170 3 CLR 99 (9 PM to Midnight) 201208040152 *** 0 CLR 90 Blue: Wind speed Kansas State Weather Data during those hours
Lessons? Lesson 1: 93% full sun on Critical Peak Days in Kansas 86% of Westar s efined Peak 93.34% Clear Full Sun 4.69% Scattered Clouds 37-50% Cloudy 1.74% Broken Clouds 63 -88% Cloudy 0.2% Overcast 100% Cloudy h l d Source: Mary Knapp, state climatologist, Kansas State University
Wind is not Wind Speed nearly as directly connected to critically hot 2. Utility Wind? days as the sun • Large wind farms have is. Home scale turbines quickly dedicated and trained fail for lack of maintenance crews maintenance. • Wind is a central baseload Wind is not a resource distributed • We have to connect to it resource. thru utilities by powerlines
Lesson 3. The Earth begins cool in the morning, heats slowly into the afternoon, and holds its heat until after sundown. Denying this lag is as dishonest as denying climate change. So how do we deal with it?
We become more valuable customers As we supply our own peaks Solar in Excess of Peak Required Storage Pre-Peak Solar
Storage in 2019 • In the last decade, automotive Li-ion battery costs have dropped by a factor of ten. • But residential storage can be the size of a refrigerator, be delivered into the garage by forklift, and be relatively crude and cheap. • Those are only electro chemical storage options. Thermal could be at the cost of water and have an infinite lifecycle of heating and chilling.
Solar with Storage Load shifting is the market. Credit to Matt Lehrman, Rocky Mountain Institute
Solar families relieve utilities of a burden • The investors most • If you were trying to capable of reducing improve the bottom distribution costs are the line of a company , solar families along the you would sell off the line…with Net metering least profitable we’ve shown there is portion of the business. • almost no risk or out-of- • In a utility business, pocket expense to the utility or other that’s peakload ratepayers. generation and delivery.
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